Hydraulic pumps produce pressurized hydraulic fluid for many purposes. For example, on construction equipment and heavy machinery hydraulic pumps produce pressurized fluid which actuates implements such as shovels, works as a pilot fluid for operating hydraulic valves, and drives hydraulic motors for fans or propulsion. On engines, hydraulic pumps can also produce pressurized fluid for actuating fuel injectors and other purposes. As a result of these many uses, hydraulic pumps are a staple commodity for construction and other heavy equipment, diesel engines, and other machinery.
The principal components of these pumps may be made from parts that are cast, or begin as stock material, and are then machined extensively to create the features, such as bores, threaded connections, grooves for O-rings, seats for bearings, galleries, etc., that are part of most hydraulic pump designs. A significant investment can be made in manufacturing each of the various components for a pump.
After a certain amount of time in service, some of the components may experience wear and cause the pump to operate inefficiently or to fail.
While some components of a pump that has been in service may have worn or failed, other components may be in very good, even like-new condition. If a pump is removed from service and discarded, but only some of its components exhibit serious wear, the investment made in the remaining components that are not seriously worn will be lost.
Remanufacturing seeks, in part, to recuperate the investment in components that are not worn in machinery that is taken out of service. In remanufacturing, the part removed from service is called a core. Typically, the transaction of selling a remanufactured part to a customer also involves taking back a new core which itself will be remanufactured and sold to another customer. Thus, there is usually one core which enters the remanufacturer's operation for each remanufactured part that leaves. In the remanufacturer's operation, the cores are broken into their various components and cleaned and inspected. Seriously worn or failed components may be discarded and replaced with new, original components. The remanufactured part is returned to service with some new components, and some components that were in place during the part's prior service. The discarded parts can be recycled to reuse the metal or other base materials.
Besides saving non-worn parts and replacing only the worn parts, a remanufacturing operation can also seek to salvage the worn parts themselves to further increase efficiency and save costs. Salvaging involves performing various operations on the worn component to bring it back to its original specifications and functionality.
Because of the very common use of hydraulic pumps on construction and other machinery as described above, because these pumps can wear rapidly, and because of the cost savings which can be achieved through remanufacturing, there is a need for developing effective salvage techniques which can be applied to facilitate remanufacturing. Besides the salvage techniques themselves, these pumps could be designed originally in a manner which better facilitates remanufacturing.